1. Field of the Invention
The present invention relates to a liquid crystal display (LCD) device, and more particularly, to a transflective LCD device.
2. Description of the Prior Art
Due to low prices and high quality of LCD devices, the LCD device is widely applied in notebooks, PDA, mobile phones, and so on. Unlike cathode ray tubes (CRTs) and electro luminescence (EL) devices, LCD devices do not emit light beams, and accordingly they are equipped with supplemental light sources. In general, the LCD devices can be classified into reflective LCD devices, transmissive LCD devices, and transflective LCD devices. A reflective LCD device is illuminated by light beams that enter the device from the front of the device. A reflective surface (such as aluminum), placed inside the LCD device, returns light beams to illuminate the LCD device. Thus, the reflective LCD device can display images to a user in front of the LCD device. A transmissive LCD device usually has a backlight assembly disposed behind a liquid crystal layer. Light beams generated by the backlight assembly selectively penetrate the liquid crystal layer, and thus the transmissive LCD device can display images to a user in front of the LCD device. A transflective LCD device can display images both in a reflective mode and in a transmissive mode.
Please refer to FIG. 1. FIG. 1 is a schematic diagram of a prior art transflective LCD device. As shown in FIG. 1, a transflective LCD device 10 comprises an upper polarizer 12, a retardation film 14, an upper glass substrate 16, a common counter electrode 18, a liquid crystal layer 20, a transparent electrode 22, a lower glass substrate 24, a light diffusing plate 26, a reflective polarizer 28, and a backlight assembly 30. The backlight assembly 30 comprises a light source 30a, a light guide plate 30b, and a light absorbing plate 30c. One side of the backlight assembly 30 is opaque. The reflective polarizer 28 is made of a multi-layer dielectric film. Therefore, light beams are partially reflected by the reflective polarizer 28 and partially transmitted by the reflective polarizer 28.
As shown in FIG. 1, ambient light beams partially enter the transflective LCD device 10. As the ambient light beams penetrate each part of the transflective LCD device 10, they are reflected by the reflective polarizer 28. After that, the reflected ambient light beams penetrate each part of the transflective LCD device 10. As a result, the transflective LCD device 10 can display images to a user 32. The transflective LCD device 10 is operated in a reflective mode. In addition, as the ambient light beams are insufficient, the light source 30a of the backlight assembly 30 generates light beams to illuminate the transflective LCD device 10. The light beams generated by the light source 30a partially penetrate the reflective polarizer 28, and each part of the transflective LCD device 10. Finally, the transflective LCD device 10 can display images to a user 32. In this way, the transflective LCD device 10 is operated in a transmissive mode.
Through the use of the opaque backlight assembly 30 as a light source, the user 32 can see images through only one side of the transflective LCD device 10. As the transflective LCD device 10 is utilized in a mobile phone with a folding section, each side of the folding section needs a piece of the transflective LCD device 10 so that the user can see images through opposite sides of the folding section. However, the folding section with two pieces of the transflective LCD device 10 will increase volume and weight of the mobile phone.
It is therefore a primary objective of the claimed invention to provide a transflective LCD device so that users can see images through opposite sides of the LCD device.
According to the claimed invention, a LCD device having a first side and a second side parallel with the first side is provided. The LCD device includes a front light source positioned on the first side of the LCD device for generating light beams, and a transflective liquid crystal panel. The transflective liquid crystal panel includes a first glass substrate located between the front light source and the second side of the LCD device, a second glass substrate located between the first glass substrate and the second side of LCD device, and a transflective layer located between the first glass substrate and the second glass substrate for reflecting and transmitting the light beams generated by the front light source. When the light beams generated by the front light source are reflected by the transflective layer and then are emitted to the first side of the LCD device, the LCD device displays images through the first side in a reflective mode, and when the light beams generated by the front light source are transmitted by the transflective layer and then are emitted to the second side of the LCD device, the LCD device displays images through the second side in a transmissive mode.
It is an advantage over the prior art that the claimed invention provides a transflective LCD device including a front light system and a transflective LCD panel. A user can see images through opposite sides of the transflective LCD device. As a result, in the claimed invention, only a single transflective LCD device is required to assemble electronic products capable of displaying images through opposite sides of the transflective LCD device, such as mobile phones. Thus, production cost is reduced, and further, volume and weight of the electronic products are also reduced.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment, which is illustrated in the multiple figures and drawings.